More than likely he's just running the BMS flash and not 100% e85. The added fueling from the flash takes care of trims and a few other things, but with 100% e85 you would run into LPFP not being able to maintain the volume required to support the HPFP after shifts.

FFTEC just posted a picture of the LPFP booster on facebook "Vishnu Performance Systems". I'm running this pump and have been for the past 3 weeks. I run 100% e85 with no LPFP codes. I was skeptical at first, but I was trapping 150+ at Shift S3ctor and didn't have any fueling issues running 100% e85.

BUT.... Regardless of what tune you're running, your DME fueling tables need to be updated to take advantage of this. Otherwise you'll still be maxing your trims.

More than likely he's just running the BMS flash and not 100% e85. The added fueling from the flash takes care of trims and a few other things, but with 100% e85 you would run into LPFP not being able to maintain the volume required to support the HPFP after shifts.

FFTEC just posted a picture of the LPFP booster on facebook "Vishnu Performance Systems". I'm running this pump and have been for the past 3 weeks. I run 100% e85 with no LPFP codes. I was skeptical at first, but I was trapping 150+ at Shift S3ctor and didn't have any fueling issues running 100% e85.

BUT.... Regardless of what tune you're running, your DME fueling tables need to be updated to take advantage of this. Otherwise you'll still be maxing your trims.

More than likely he's just running the BMS flash and not 100% e85. The added fueling from the flash takes care of trims and a few other things, but with 100% e85 you would run into LPFP not being able to maintain the volume required to support the HPFP after shifts.

FFTEC just posted a picture of the LPFP booster on facebook "Vishnu Performance Systems". I'm running this pump and have been for the past 3 weeks. I run 100% e85 with no LPFP codes. I was skeptical at first, but I was trapping 150+ at Shift S3ctor and didn't have any fueling issues running 100% e85.

BUT.... Regardless of what tune you're running, your DME fueling tables need to be updated to take advantage of this. Otherwise you'll still be maxing your trims.

Does the PROcede log low fuel pressure? Are you sure you needed the inline pump? With methanol injection it should not be required for your power levels. Without methanol injection you might have had a low fuel pressure issue but the codes alone would not really indicate that. You would need to log low fuel pressure to see if its dropping at higher RPM. BMS found when it drops below 50psi or so bad things happen.

More than likely he's just running the BMS flash and not 100% e85. The added fueling from the flash takes care of trims and a few other things, but with 100% e85 you would run into LPFP not being able to maintain the volume required to support the HPFP after shifts.

FFTEC just posted a picture of the LPFP booster on facebook "Vishnu Performance Systems". I'm running this pump and have been for the past 3 weeks. I run 100% e85 with no LPFP codes. I was skeptical at first, but I was trapping 150+ at Shift S3ctor and didn't have any fueling issues running 100% e85.

BUT.... Regardless of what tune you're running, your DME fueling tables need to be updated to take advantage of this. Otherwise you'll still be maxing your trims.

A couple people are toying with 100% e85. Not suggested unless you have a Flex fuel wires. Its a good idea to upgrade your fuel pump (hpfp and LPFP)

I tihnk above 60%/40% E95/93(91) without flex fuel wires will trip ecu sensors. I dont even think our fuel pumps can handle it 100% without maxing them out.

This is not true. You can do 100% E85 with BMS flash and a JB4 without an upgraded fuel pump. With FBO and larger turbos you will need upgraded fuel pump. The pump is at its limits with stock turbos and 100% E85, but it can still do it in most cases without lean outs as I understand it. If you need upgraded pump you can source a Walbro E85 pump for $180 plus $20 of fittings and that solves the LPFP issue. There is a DIY out.

Does the PROcede log low fuel pressure? Are you sure you needed the inline pump? With methanol injection it should not be required for your power levels. Without methanol injection you might have had a low fuel pressure issue but the codes alone would not really indicate that. You would need to log low fuel pressure to see if its dropping at higher RPM. BMS found when it drops below 50psi or so bad things happen.

Mike

Debug byte 4 logs fuel pressure and the output should stay above 2v under boost. When it drops below 2v, the DME will through the LPFP code.

Did I need the pump? No... I could have dump Methanol at the engine and it probably would have been fine. But most people including myself doesn't want to use Methanol, at least in my case not all the time.

Honestly, I haven't taken the time to log debug byte 4 sense I got home. With the rain and cooler weather, it's really hard to log due to wheel spin. I'm sure there will be a thread specifically for this and technical data will be provided.

This is not true. You can do 100% E85 with BMS flash and a JB4 without an upgraded fuel pump. With FBO and larger turbos you will need upgraded fuel pump. The pump is at its limits with stock turbos and 100% E85, but it can still do it in most cases without lean outs as I understand it. If you need upgraded pump you can source a Walbro E85 pump for $180 plus $20 of fittings and that solves the LPFP issue. There is a DIY out.

I think the Walbro was a good aftermarket solution if your LPFP was actually failing, but I think they found that pump alone was still dropping pressure because it couldn't maintain the surge volume required at peak torque.

I think the Walbro was a good aftermarket solution if your LPFP was actually failing, but I think they found that pump alone was still dropping pressure because it couldn't maintain the surge volume required at peak torque.

Was a good aftermarket solution? Its an OE solution that can outflow the HPFP. It is not dropping pressure anywhere. Terry's RB car on 100% E98 (requires more fueling than 100% E85) is not losing low pressure anywhere in the rev range. That includes peak torque, which btw is not where you would max a low pressure pump at (this happens at peak power). He is making well over 500whp with no meth and the bad bsfc that comes along with stock housings. It seems you have evidence this is not the case though. I'd love to see it and get down to the bottom of this since I am considering upgrading the low pressure system and have been waiting to see the results of both solutions.

That being said, I was hoping for something a little more professional than a booster pump slapped on to compensate for the stock pump. I will wait to pass judgment on this inline booster pump, but to me the concept sounds more like an "aftermarket solution" that doesn't integrate properly with the OE fuel system. If the stock pump doesn't flow enough it should be replaced with one that does. Maybe I am missing something, guess we will see.

Was a good aftermarket solution? Its an OE solution that can outflow the HPFP. It is not dropping pressure anywhere. Terry's RB car on 100% E98 (requires more fueling than 100% E85) is not losing low pressure anywhere in the rev range. That includes peak torque, which btw is not where you would max a low pressure pump at (this happens at peak power). He is making well over 500whp with no meth and the bad bsfc that comes along with stock housings. It seems you have evidence this is not the case though. I'd love to see it and get down to the bottom of this since I am considering upgrading the low pressure system and have been waiting to see the results of both solutions.

That being said, I was hoping for something a little more professional than a booster pump slapped on to compensate for the stock pump. I will wait to pass judgment on this inline booster pump, but to me the concept sounds more like an "aftermarket solution" that doesn't integrate properly with the OE fuel system. If the stock pump doesn't flow enough it should be replaced with one that does. Maybe I am missing something, guess we will see.

Well, considering I didn't do the testing I can't provide you all the details regarding BMS's testing, but I did talk with Terry at Shift S3ctor. I was under the assumption that they were still seeing fueling issues with e85 at higher power levels, but you seem to be very knowledgeable regarding this so please feel free to correct me if I'm wrong.

The ability of a fuel delivery system to maintain a specific pressure (in PSI) is an important factor when analyzing a fuel system. It should not be confused with volumetric or ability to deliver a specific amount (in Gal. per minute or Litters per minute) of fuel. As a rule of thumb, when a system can not maintain a specific pressure, the vehicle will probably run very bad or not run at all. On the other hand, it is quite common to see vehicles with good fuel pressure and have performance problems due to a lack of fuel volume. Good fuel volume is the systemís ability to maintain a specific quantity or volume regardless of vehicle operation and that is the key point that everyone seems to overlook.

When two (or more) pumps are arranged in serial their resulting pump performance curve is obtained by adding their heads at the same flow rate as indicated in the figure below.

Pumps in series are used to overcome larger system head loss than one pump can handle alone.

* For two identical pumps in series the head will be twice the head of a single pump at the same flow rate - as indicated in point 2.

With a constant flowrate the combined head moves from 1 to 2.

Note! In practice the combined head and flow rate moves along the system curve to point 3.

* Point 3 is where the system operates with both pumps running
* Point 1 is where the system operates with one pump running

So I'm not saying that for most the replacement of the LPFP will fix the issue if the volume of fuel is increased by the replacement of the old pump. But when your system demands more volume that a single pump can deliver, adding a booster pump will increase the flow rate required to sustain the HPFP at peak demand.

Was a good aftermarket solution? Its an OE solution that can outflow the HPFP. It is not dropping pressure anywhere. Terry's RB car on 100% E98 (requires more fueling than 100% E85) is not losing low pressure anywhere in the rev range. That includes peak torque, which btw is not where you would max a low pressure pump at (this happens at peak power). He is making well over 500whp with no meth and the bad bsfc that comes along with stock housings. It seems you have evidence this is not the case though. I'd love to see it and get down to the bottom of this since I am considering upgrading the low pressure system and have been waiting to see the results of both solutions.

That being said, I was hoping for something a little more professional than a booster pump slapped on to compensate for the stock pump. I will wait to pass judgment on this inline booster pump, but to me the concept sounds more like an "aftermarket solution" that doesn't integrate properly with the OE fuel system. If the stock pump doesn't flow enough it should be replaced with one that does. Maybe I am missing something, guess we will see.

I think I finally got this. There is a high pressure fuel pump and a low fuel pressure pump. The low fuel pressure pump brings fuel to the high fuel pressure pump. The idea of the booster pump is to help the low fuel pressure pump bring more fuel to the high fuel pressure pump while keeping the orignal low fuel pressure pump in the tank. The other solution is to install a stronger low fuel pressure pump in the tank and not have an extra booster pump at all. So what is better???

I was under the assumption that they were still seeing fueling issues with e85 at higher power levels, but you seem to be very knowledgeable regarding this so please feel free to correct me if I'm wrong.

I don't really understand are you talking about low fuel pressure flow or high fuel pressure flow? They are different things.

I don't really understand are you talking about low fuel pressure flow or high fuel pressure flow? They are different things.

Yes, two very different things. Your LPFP feeds the HPFP and if it can't maintain the required pressure, your DME will trigger a LPFP code. Replacing the LPFP could increase the pressure and volume, but eventually you will exceed the volume required to supply the HPFP with a single pump.

Yes, two very different things. Your LPFP feeds the HPFP and if it can't maintain the required pressure, your DME will trigger a LPFP code. Replacing the LPFP could increase the pressure and volume, but eventually you will exceed the volume required to supply the HPFP with a single pump.

Cars running the bigger in tank pump are getting a LPFP code and those running the booster pump are not? ign335i said using the single larger pump prevented the LPFP code too.

Well, considering I didn't do the testing I can't provide you all the details regarding BMS's testing, but I did talk with Terry at Shift S3ctor. I was under the assumption that they were still seeing fueling issues with e85 at higher power levels, but you seem to be very knowledgeable regarding this so please feel free to correct me if I'm wrong.

The ability of a fuel delivery system to maintain a specific pressure (in PSI) is an important factor when analyzing a fuel system. It should not be confused with volumetric or ability to deliver a specific amount (in Gal. per minute or Litters per minute) of fuel. As a rule of thumb, when a system can not maintain a specific pressure, the vehicle will probably run very bad or not run at all. On the other hand, it is quite common to see vehicles with good fuel pressure and have performance problems due to a lack of fuel volume. Good fuel volume is the system’s ability to maintain a specific quantity or volume regardless of vehicle operation and that is the key point that everyone seems to overlook.

When two (or more) pumps are arranged in serial their resulting pump performance curve is obtained by adding their heads at the same flow rate as indicated in the figure below.

Pumps in series are used to overcome larger system head loss than one pump can handle alone.

* For two identical pumps in series the head will be twice the head of a single pump at the same flow rate - as indicated in point 2.

With a constant flowrate the combined head moves from 1 to 2.

Note! In practice the combined head and flow rate moves along the system curve to point 3.

* Point 3 is where the system operates with both pumps running
* Point 1 is where the system operates with one pump running

So I'm not saying that for most the replacement of the LPFP will fix the issue if the volume of fuel is increased by the replacement of the old pump. But when your system demands more volume that a single pump can deliver, adding a booster pump will increase the flow rate required to sustain the HPFP at peak demand.

Refer to either of the threads on the other two forums regarding the E85 pump. The data is right there. I cannot cross post it or I could get banned.

The info you copied somewhere from the internet is correct. What that stipulates is that running pumps in series jacks up the pressure and thus only flows more if you are losing pressure. The upgraded LPFP is NOT losing pressure. Are you suggesting we raise the stock pressure limit (I am not necessarily opposed, just genuinely curious)?

Btw, if you go back to the website you were just on and look at the schematic right below it, you will see that two pumps in parallel is a much more effective method of increasing flow rather than pressure... Kind of surprised you didn't post that.

I think I finally got this. There is a high pressure fuel pump and a low fuel pressure pump. The low fuel pressure pump brings fuel to the high fuel pressure pump. The idea of the booster pump is to help the low fuel pressure pump bring more fuel to the high fuel pressure pump while keeping the orignal low fuel pressure pump in the tank. The other solution is to install a stronger low fuel pressure pump in the tank and not have an extra booster pump at all. So what is better???

Correct. We have yet to see which is better. They both get the job done, it really just comes down to price, ease of install, etc. Imho replacing the low capacity pump is preferable to slapping another pump on after it.

Quote:

Originally Posted by Wedge1967

Replacing the LPFP could increase the pressure and volume, but eventually you will exceed the volume required to supply the HPFP with a single pump.

This statement is patently false. Are you seriously saying there isn't a single pump in the world that can flow enough to feed our HPFP??? There is and its already out there running. Its the pump Walbro designed for running E85 on which there are DIYs for... Even if its not that pump, to say there isn't a single pump that can flow enough is just plain wrong.

Refer to either of the threads on the other two forums regarding the E85 pump. The data is right there. I cannot cross post it or I could get banned.

The info you copied somewhere from the internet is correct. What that stipulates is that running pumps in series jacks up the pressure and thus only flows more if you are losing pressure. The upgraded LPFP is NOT losing pressure. Are you suggesting we raise the stock pressure limit (I am not necessarily opposed, just genuinely curious)?

Btw, if you go back to the website you were just on and look at the schematic right below it, you will see that two pumps in parallel is a much more effective method of increasing flow rather than pressure... Kind of surprised you didn't post that.

Correct. We have yet to see which is better. They both get the job done, it really just comes down to price, ease of install, etc. Imho replacing the low capacity pump is preferable to slapping another pump on after it.

This statement is patently false. Are you seriously saying there isn't a single pump in the world that can flow enough to feed our HPFP??? There is and its already out there running. Its the pump Walbro designed for running E85 on which there are DIYs for... Even if its not that pump, to say there isn't a single pump that can flow enough is just plain wrong.

You make a good argument, but I'm currently running an inline booster and have no issues with LP codes running 100% e85. I'm not saying the other solution isn't a viable solution, it's an optional solution. Yes, I could have replaced my LPFP with a new one, but others did so and were still having the same issue. For me, adding the booster pump fixed the issue. So to me that was a good indication that it wasn't a pressure related issue, but more of a volume related issue at peak demand. So, you can argue your point, or you can go buy one, test it, and provide a conclusion. Until then, your just making assumptions.

Cars running the bigger in tank pump are getting a LPFP code and those running the booster pump are not? ign335i said using the single larger pump prevented the LPFP code too.

No one is telling you that you can't go out and buy the biggest pump you can find and customize it to fit your car. You have options and that's why I can't understand why people keep making a big deal out of this. If your LPFP is failing, replace it. You can replace it using the DIY with the Walbro E85 pump, or pickup a new OEM. Or you now have the option of running a plug-n-play inline booster pump that goes inside your tank. It's very simple, but you have to make your own choice. I can tell you all day long that it works for me and I have it installed and have tested it. Or you can listen to someone assumptions because they are skeptical, haven't tested it, but still think they know better. Trust me, I was skeptical also... but again, it works...

No one is telling you that you can't go out and buy the biggest pump you can find and customize it to fit your car. You have options and that's why I can't understand why people keep making a big deal out of this. If your LPFP is failing, replace it. You can replace it using the DIY with the Walbro E85 pump, or pickup a new OEM. Or you now have the option of running a plug-n-play inline booster pump that goes inside your tank. It's very simple, but you have to make your own choice. I can tell you all day long that it works for me and I have it installed and have tested it. Or you can listen to someone assumptions because they are skeptical, haven't tested it, but still think they know better. Trust me, I was skeptical also... but again, it works...

Hi, where is this DIY for the Walbro E85 pump? I searched in the DIY section but couldnt find it.